JPH1056706A - Forced ventilated electronic appliance box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a forced ventilated electric appliance box which can prevent the dropping of the rated output caused by the different between the cooled temperatures of cooled parts. SOLUTION: In a transformer box 1A, a shield plate 7A having a square shape in its top view is provided at the lower end position of the coil of a transformer 2. An air reservoir 9A is formed between the shield plate 7A and the bottom face of the box 1A. Cooling air is introduced to the air reservoir 9A from air inlets 5A and 5B respectively formed in the lower sections of a front door 3A and rear door 3B and, in the air reservoir 9A, the air pressure of the cooling air is made uniform so as to make uniform the flow velocity of the cooling air flowing upward through the gap formed between the inner periphery of the shield plate 7A and the outer periphery of the coil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forced ventilation type electric equipment box.

[0002]

2. Description of the Related Art FIG. 18 is a left side view showing an example of a conventional forced-ventilated electric equipment box containing an air-cooled transformer, which is installed adjacent to a wall of an electric room of a building. Also, FIG.
Is an RR cross-sectional view of FIG. 18, and FIG. 20 is an SS cross-sectional view of FIG.

In FIG. 18, FIG. 19 and FIG. 20, inside a transformer box 1A which is installed close to the wall of an electric room 6 of a building with respect to the upper surface of a gantry 1a shown in FIG. An air-cooled transformer 2 connected to the load side of a three-phase inverter (not shown) is mounted.

[0004] A pair of front doors 3A are mounted on the right side of the transformer box 1A as shown in Fig. 20 via packing (not shown) on the right side in Fig. 18, and also on the rear side of the transformer box 1A. One back door 3B is attached via a packing (not shown).

At the lower ends of the front door 3A and the rear door 3B, in the side view (not shown) of FIG. 18, strip-shaped air inlets 5A and 5B are formed.
An air filter (not shown) is detachably attached to 5B.

[0006] Transformer 2 is connected to one side of iron core 2e by R
The phase coil 2a is inserted as described later in detail in the enlarged cross-sectional view of FIG. 21. Similarly, the S-phase coil 2b is inserted into the center of the iron core 2e, and further, the other side of the iron core 2e is inserted into the core 2e. The T-phase coil 2c is inserted.

A primary terminal 2f and a secondary terminal 2g are provided at the upper end of the transformer 2 with respect to the rear side for three phases, respectively.
An exhaust port 1b is provided at the center of the ceiling plate of the transformer box 1, and an exhaust fan 4 is attached to a lower surface of the exhaust port 1b.

Next, FIG. 21 shows the coil 2a shown in FIG.
FIG. 22 is an enlarged detailed view of (2b, 2c), and FIG. 22 is a sectional view taken along line TT of FIG. 21 and 22, a primary coil 12 is inserted outside the iron core 11 through a plurality of spacing pieces (not shown), and a secondary coil 13 is also inserted outside the primary coil 12 through a spacing piece (not shown). Has been inserted. This coil 13
An insulating layer 11a is formed on the outside of the device via a not-shown spacing piece.

As a result, a substantially rectangular cylindrical ventilation path 14 through which cooling air flows is formed between the inner core 11 and the outer coil 12, and the air passage 14 is formed between the inner core 11 and the outer coil 13. A ventilation path 15 is also formed between the coil 13 and the insulating layer.
An air passage 16 is formed coaxially between 11a.

The transformer box 1A has a wide inspection space in front so that the front door 3A can be opened to perform maintenance and inspection of the inside. Further, the electric room may be installed with one side surface in contact with a corner of the wall.

In the transformer box constructed as described above, as the internal air is exhausted by the exhaust fan 4, the cooling air flows from the transformer 2 through the intake ports 5A and 5B at the lower front and rear of the box.
Flows underneath. This cooling air flows into the transformer 2
Are heated by the coils 2a, 2b, 2c and the iron core 11 and rise, and are drawn into the exhaust fan 4 and discharged to the outside.

In this process, a part of the cooling air rising from the lower side of the transformer 2 is dissipated by the iron core 11 shown in FIGS.
And each ventilation path formed between each coil 2a, 2b, 2c
It flows through 14, 15, and 16 and is heated and rises. Another part of the cooling air gradually rises between the coils and between the coils and the inner surface of the box.

[0013]

However, in such a forced-ventilation-type electric equipment box installed in an electric room and containing a transformer, the space between the rear door 3B and the wall surface of the electric room 6 is shown in FIG. As shown by an arrow V2 in FIG. 20, the flow rate of the cooling air sucked into the lower end of the transformer box 1A through the ventilation port 5B is shown in FIG.
It depends on the left and right.

That is, the wind pressure of the cooling air in the left vent 5B is higher than the wind pressure Vp2 in the right vent 5B, and the static pressure entering the coil is such that the left static pressure Sp1 is greater than the right static pressure Sp2. Get higher.

Then, the cooling temperatures of the coils 2a, 2b, 2c vary, and, for example, the rising temperature of the T-phase coil 2c becomes the highest, and the rating (kVA) of the transformer 2 is restricted by this temperature. Therefore, an object of the present invention is to provide a forced ventilation type electric equipment box capable of preventing a decrease in rated output due to a difference in cooling temperature of a cooling part.

[0016]

According to the first aspect of the present invention, an electric device is housed in a box whose outer periphery is closed, a cooling air inlet is formed in a lower portion of the box, and an upper end of the box is provided. In the forced ventilation type electric equipment box provided with an exhaust fan,
A shield is formed laterally inside the box so that the outer periphery of the side surface of the electric device is loosely fitted on the inner periphery and forms a lower air reservoir for storing the cooling air sucked from the suction port.

The forced ventilation type electric equipment box according to claim 2 is characterized in that the electric equipment is a transformer and the inner periphery of the shield is opposed to the lower end of the coil of the transformer.

Further, in the forced ventilation type electric equipment box according to the third aspect of the present invention, the shielding member is a square-shaped shielding plate.

The forced ventilation type electric equipment box according to claim 4 is characterized in that the shielding member has a rectangular cylindrical shape and the upper end is opposed to the lower end of the coil of the transformer.

In the forced ventilation type electric equipment box according to the fifth aspect of the present invention, a gap adjuster is protruded from a portion of an inner periphery of the shield facing a curved surface portion of an outer periphery of a coil of a transformer. It is characterized by having done.

Further, the forced ventilation type electric equipment box according to the invention of claim 6 is characterized in that the box body has one side of the back side and one side face adjacent to the wall of the installation place.

According to the first aspect of the present invention, the flow rate of the cooling air that rises from the gap formed on the outer periphery of the electric device and the inner periphery of the shield and cools the electric device is increased by the above means. The pressure is made uniform by the air reservoir.

Also, in the invention according to claim 2,
The flow velocity of the cooling air that rises from inside and outside the coil of the transformer and cools the coil is made uniform by an air reservoir in which the internal pressure becomes uniform.

According to the third aspect of the present invention,
The flow rate of the cooling air flowing between the outer periphery of the coil of the transformer and the inner periphery of the shield plate and flowing through the inside of the coil to cool the coil is made uniform by an air reservoir in which the internal pressure becomes uniform.

In the invention according to claim 4,
The flow velocity of the cooling air that flows between the outer periphery of the transformer coil and the inner periphery of the rectangular tubular shield and through the inside of the coil to cool the coil by ascending is made uniform by the air reservoir that makes the internal pressure uniform. Become

In the invention according to claim 5,
Cooling air that flows between the outer periphery of the coil of the transformer and the shield and through the inside of the coil and rises to cool the coil is raised from an air reservoir having an even internal pressure and the flow rate is adjusted by the gap adjuster.

Further, in the invention according to claim 6, the coils of the transformer having different cooling effects depending on the installation conditions are uniformly cooled by the cooling air rising from the air reservoir.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a forced ventilation type electric equipment box according to the present invention will be described below with reference to the drawings. FIG.
1 is a left side view showing a first embodiment of a forced ventilation type electric equipment box according to the present invention, which corresponds to FIG. 18 shown in the prior art, corresponds to claim 1, and FIG. FIG. 3 is a sectional view taken along the line A and also corresponds to FIG. 19, and FIG. 3 is a sectional view taken along the line BB of FIG. 2 and also corresponding to FIG.

FIGS. 1, 2 and 3 differ from FIGS. 18, 19 and 20 shown in the prior art in that the outer periphery of the coil of the transformer is located below the transformer box 1A. By providing a shielding plate that regulates the flow of the rising cooling air, and forming an air reservoir below the shielding plate,
22 to FIG. Therefore, these FIGS.
The same elements as those described above are denoted by the same reference numerals and description thereof will be omitted.

That is, in FIGS. 1, 2 and 3,
In the lower part of the transformer box 1A, a shield plate 7A having a substantially square shape in FIG. 3 is provided horizontally at the height of the lower ends of the coils 2a, 2b, 2c of the transformer 2. The shielding plate 7A is made of a glass fiber reinforced plastic plate having a thickness of about 10 mm. Therefore, between the shielding plate 7A and the bottom surface of the transformer box 1A, an air reservoir 9A for storing the cooling air flowing from the vents 5A and 5B is formed.

In the forced ventilation type electric equipment box configured as described above, for example, it is installed at the corner of the wall of the electric room 6, and as shown in FIG. Even when the pressure (that is, the flow rate) of the cooling air flowing through the intake port 5B is different between the left and right, the air reservoir 9A having a larger flow path cross-sectional area than the intake port 5B causes R, S , T phase is almost constant irrespective of the site.

Therefore, these coils 2a, 2b,
The flow rate of the cooling air flowing upward through the inside and the outer periphery of 2c can be made substantially uniform, and the difference in temperature rise between each coil can be reduced.

Note that a band-shaped shielding plate is protruded from a position at the same height as the shielding plate 7A inside the lower part of the front door 3A and the rear door 3B, and the inside of these shielding plates is shielded by the shielding plate 7A. By contacting the front end and the rear end of the coil, the leakage of the cooling air flowing into the air reservoir 9A from the intake ports 5A and 5B is suppressed, and the flow rate of the cooling air for cooling the coil is prevented from being reduced, and the cooling effect of the coil is reduced. May be raised.

Next, FIG. 4 is a left side view showing a second embodiment of the forced ventilation type electric equipment box of the present invention, and is a view corresponding to FIG. 1, and FIG. 5 is a cross-sectional view taken along line CC of FIG. 7 is a view corresponding to FIG. 2, FIG. 6 is a cross-sectional view taken along line D-D of FIG. 5, and is a view corresponding to FIG. 3, and FIG.
FIG. 7B is an enlarged detail view of a portion F in FIG. 6.

FIGS. 4, 5, 6, and 7 (a), (b)
In FIGS. 1, 2 and 3 shown in the first embodiment,
The difference from FIG. 1, FIG. 2 and FIG. 3 is that an air flow adjusting plate is added to the shield plate 7A provided horizontally below the transformer box 1A shown in FIG. And FIG. Therefore, the same elements as those in FIGS. 1, 2 and 3 are denoted by the same reference numerals and description thereof will be omitted.

That is, on the front and rear upper surfaces of the shielding plate 7A shown in FIGS. 1, 2 and 3, the positions facing the phase between the coils 2a and 2b and the positions facing the phase between the coils 2b and 2c are provided. On the other hand, a substantially arrow-shaped air volume adjusting plate 8A is placed.

As shown in FIG. 7 (a), a pair of grooves 8a are formed in the air volume adjusting plate 8A on the bottom side in the shape of an arrow. The air flow adjusting plate 8A is fixed to the shielding plate 7A so as to be adjustable in the direction of the arrow with a fastener inserted into the hole.

On the other hand, before and after the left end of the R-phase coil 2a in FIG. 6 and before and after the right end of the T-phase coil 2c in FIG.
Is mounted. The air volume adjusting plate 8B also has grooves 8b formed on two orthogonal sides, and these air volume adjusting plates 8B are inserted into the grooves 8b and the ends are formed on the left and right sides of the shielding plate 7A on the front door side. A fastener screwed into the screw hole is fixed so as to be adjustable in the direction of the arrow.

As described above, the shielding plate 7A and the air volume adjusting plate 8A,
8B is incorporated in the transformer box 1A, the rated load is applied and the temperature rise test is performed as one item of the shipping test.
After adjusting the positions of A and 8B, they are fixed.

For example, the S-phase coil 2b located at the center
When the temperature rise value of the air conditioner is the largest,
By bringing the arc-shaped end of B closer to the outer periphery of the coils 2a and 2c, the flow rate of the cooling air rising on the facing surface is suppressed,
The flow rate at the curved surface of the S-phase coil 2b is increased.

Therefore, in the forced ventilation type electric equipment box configured as described above, the temperature rise of the coil of each phase can be leveled, so that a decrease in the rated output due to the temperature difference can be suppressed. . In the above-described embodiment, the pair of air volume adjusting plates 8A at the intermediate portion is formed by a single plate having left and right arrow portions protruding left and right.
It may be a part.

FIG. 8 is a left side view showing a third embodiment of a forced ventilation type electric equipment box according to the present invention.
9, FIG. 9 is a sectional view taken along the line GG of the figure, and also a figure corresponding to FIGS. 2 and 5, and FIG. 10 is a sectional view taken along the line HH of FIG. It is a corresponding figure.

8, 9 and 10 are different from FIGS. 1, 2 and 3 shown in the first embodiment and FIGS. 4, 5 and 6 shown in the second embodiment. Is the transformer box 1A
The transformer 2 is placed on the upper surface of the air reservoir 9B formed at the lower part of the air reservoir 9B, and the transformer 2 is mounted on the upper surface of the air reservoir 9B.
1, 2, 3, 4, 5, and 6 are the same as those of FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. Therefore, the same elements as those in FIGS. 1, 2, and 3 and FIGS. 4, 5, and 6 are denoted by the same reference numerals, and description thereof will be omitted.

That is, a pair of angle irons 9a are provided horizontally above the air reservoir 9B, and the lower ends of the mounting legs of the transformer 2 are mounted and fixed to the center of these angle irons 9a. I have.

A rectangular opening opening upward from the air reservoir 9B is formed around the lower end of the mounting leg of the transformer 2.
Around this opening, a partition plate 9b constituting the ceiling of the air reservoir 9B is provided as shown in FIG.

The upper surface of the partition plate 9b on the opening side is shown in FIG.
The shield frame 7B formed in the shape of a short rectangular tube is erected, and is fixed to the partition plate 9b by a flange formed at the lower end of the shield frame 7B. A slight gap is formed between the inner periphery of the upper end of the shielding frame 7B and the outer periphery of each of the coils 2a, 2b, 2c.

In the transformer box 1B in which the shielding frame 7B is housed and the air reservoir 9B is formed, the air reservoir 9B is formed.
B and a rectangular cylindrical space having a convex cross section formed by the shielding frame 7B become a substantial air reservoir, so that the volume of the air reservoir can be increased, and the air has flowed in through the air inlets 5A, 5B. The flow rate at which the cooling air flows upward through the outer periphery of each of the coils 2a, 2b, 2c can be further leveled at each portion, and the function of the air reservoir can be improved.

By increasing the height of the shielding frame 7B,
Not only the cooling effect of each coil by the cooling air rising between the inner surface of the shielding frame 7B and the coils 2a, 2b, 2c can be improved, but also the cooling air can be used as a laminar flow, and a layer on the surface of the coil can be formed. The flow cooling area and the flow rate of the cooling air can be increased, and the temperature of the coil can be further reduced.

The upper end of the shielding plate 7B is slightly curved outward to prevent a sudden change in the cross-sectional area of the flow path of the cooling air, thereby preventing the turbulent flow of the cooling air rising from the upper end of the shielding plate 7B. It may be further reduced.

Next, FIG. 11 is a left side view showing a fourth embodiment of a forced ventilation type electric equipment box according to the present invention, corresponding to FIGS. 1, 4 and 8, and FIG. FIG. 13 is a sectional view corresponding to FIGS. 2, 5 and 9; FIG. 13 is a sectional view taken along the line KK in FIG. is there.

FIGS. 11, 12 and 13 are different from FIGS. 8, 9 and 10 shown in the third embodiment described above in that the upper part of the air reservoir 9B formed at the lower end of the transformer box is shown. 8, 9 and 10 are the same as those in FIGS. 8, 9 and 10 except for the planar shape of the shielding frame erected on the upper surface of the partition plate 9b provided in the second embodiment. Therefore, the same elements as those in FIGS. 8, 9 and 10 are denoted by the same reference numerals and description thereof will be omitted.

That is, the shielding frame 7C mounted on the upper surface of the partition plate 9b is a simple rectangle in FIG. 10 of the third embodiment, but shows a plan view of this embodiment.
In FIG. 13, the portions facing the curved surfaces of the corners of the coils of each phase protrude.

In the forced ventilation type electric equipment box having the shielding plate 7C as described above, the flow rate of the cooling air flowing upward from the air reservoir 9B along the outer periphery of the coil of each phase is entirely changed at the curved surface portion and the linear portion. Since it can be made uniform over the circumference, the cooling effect of the coil can be improved.

Next, FIG. 14 is a left side view showing a fifth embodiment of the forced ventilation type electric equipment box of the present invention, and FIGS.
8 and FIG. 11, FIG. 15 is a sectional view taken along line LL of FIG. 14, and also corresponds to FIG. 2, FIG. 5, FIG. 9 and FIG.
FIG. 16 is a sectional view taken along line MM of FIG.
FIG. 14 is a view corresponding to FIGS. 10 and 13.

FIGS. 14, 15 and 16 are different from FIGS. 8, 9 and 10 shown in the third embodiment in that the curved surface portions of the respective coils of the shielding frame 7B shown in FIG. The air volume adjusting plate 8 shown in detail in FIG.
The other parts are the same as those in FIGS. 8, 9 and 10 by providing C and 8D.

That is, the partition plate 9 at the upper end of the air reservoir 9B
At the upper end on the inner side of the shielding frame 7B placed on the upper surface of the coil b, a pair of arrow-shaped air volume adjusting plates 8C is provided between each phase with respect to the portions facing the curved surfaces of the coils 2a, 2b, 2c. Installed with bolts. An arrow-shaped airflow adjusting plate 8D having a right-angled tip is fixed with four bolts to a portion facing the curved surface portion on the left end of the R-phase coil 2a and the curved surface portion on the right side of the T-phase coil 2c. ing. Therefore, helicerts shown by broken lines in FIGS. 17A and 17B are inserted into the bolt holes of the air volume adjusting plates 8C and 8D.

As described above, also in the forced ventilation type electric equipment box in which the air volume adjusting plates 8C and 8D are attached to the shielding frame 7B, the cooling air flowing upward from the air reservoir 9B along the outer periphery of the coil of each phase. Since the flow rate can be made uniform over the entire circumference at the curved surface portion and the linear portion, the cooling effect of the coil can be improved.

In the above embodiment, the electric equipment housed in the box and cooled by the cooling air rising from the air reservoir is described as a transformer, but may be a reactor, for example. In the same manner, cooling can be performed uniformly.

[0059]

As described above, according to the first aspect of the present invention,
Electrical equipment is housed in a box whose outer periphery is closed, a cooling air intake port is formed in the lower part of the box, and a forced ventilation type electrical equipment box in which an exhaust fan is provided at the upper end of the box is used for the electrical equipment. The outer periphery of the electrical equipment is loosely fitted to the inner periphery, and a shield that forms an air reservoir for storing cooling air sucked from the suction port on the lower side is laid horizontally inside the box, so that the outer periphery of the electric device and the shield The flow rate of the cooling air that rises from the gap formed on the inner circumference and cools the electrical equipment is made uniform by the air reservoir that makes the internal pressure uniform. It is possible to obtain a forced-ventilation-type electric equipment box capable of preventing the drop.

According to the second aspect of the present invention, the electric device is a transformer, and the inner periphery of the shield is opposed to the lower end of the coil of the transformer, so that the shield rises from inside and outside the coil of the transformer. Forced ventilation type electric equipment that can reduce the rated output due to the difference in cooling temperature of the cooling part because the flow rate of cooling air that cools the coil is made uniform by the air reservoir that makes the internal pressure uniform. You can get a box.

According to the third aspect of the present invention, the shielding member is a square-shaped shielding plate, so that between the outer periphery of the coil of the transformer and the inner periphery of the shielding plate and inside the coil. The flow rate of the cooling air that cools the coil by rising through it is made uniform by the air reservoir that makes the internal pressure uniform, so that the rated output can be prevented from lowering due to the difference in cooling temperature at the cooling part. A forced ventilation type electric equipment box can be obtained.

According to the fourth aspect of the present invention, the shielding member has a rectangular cylindrical shape, and the upper end is opposed to the lower end of the coil of the transformer, so that the outer periphery of the coil of the transformer and the rectangular cylindrical shape are shielded. The flow rate of the cooling air that cools the coil by flowing up through the inside of the coil and inside the coil to cool the coil is made uniform by the air reservoir that makes the internal pressure uniform. Accordingly, it is possible to obtain a forced ventilation type electric equipment box capable of preventing a decrease in rated output.

According to the fifth aspect of the present invention, the gap adjusting tool is provided so as to protrude from a portion of the inner periphery of the shield which faces the outer curved surface of the coil of the transformer. Since the cooling air that flows through the space between the outer periphery of the coil of the vessel and the shield and through the inside of the coil and ascends to cool the coil, the internal pressure rises from the uniform air reservoir and the flow rate is adjusted by the gap adjuster,
It is possible to obtain a forced-ventilation-type electric equipment box that can prevent a decrease in rated output due to a difference in cooling temperature between cooling portions.

Further, according to the invention described in claim 6,
Even if one side of the back side and one side of the box is adjacent to the wall of the installation location, the coil of the transformer with a different cooling effect due to this installation condition was uniformly cooled by the cooling air rising from the air reservoir, It is possible to obtain a forced-ventilation-type electric equipment box that can prevent a decrease in rated output due to a difference in cooling temperature between cooling portions.

[Brief description of the drawings]

FIG. 1 is a left side view showing a first embodiment of a forced ventilation type electric equipment box of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a left side view showing a second embodiment of a forced ventilation type electric equipment box of the present invention.

FIG. 5 is a sectional view taken along line CC of FIG. 4;

FIG. 6 is a sectional view taken along line DD of FIG. 5;

7A is an enlarged detailed view of a portion E in FIG. 6, and FIG.
FIG.

FIG. 8 is a left side view showing a third embodiment of a forced ventilation type electric equipment box according to the present invention.

FIG. 9 is a sectional view taken along line GG of FIG. 8;

FIG. 10 is a sectional view taken along the line HH in FIG. 9;

FIG. 11 is a left side view showing a fourth embodiment of the forced ventilation type electric equipment box of the present invention.

FIG. 12 is a sectional view taken along the line JJ of FIG. 11;

FIG. 13 is a sectional view taken along the line KK of FIG. 12;

FIG. 14 is a left side view showing a fifth embodiment of the forced ventilation type electric equipment box of the present invention.

FIG. 15 is a sectional view taken along line LL of FIG. 14;

FIG. 16 is a sectional view taken along line MM of FIG. 15;

17A is an enlarged detailed view of a P part in FIG. 16, and FIG. 17B is an enlarged detailed view of a Q part in FIG.

FIG. 18 is a left side view showing an example of a conventional forced ventilation type electric equipment box.

FIG. 19 is a sectional view taken along line RR of FIG. 18;

20 is a sectional view taken along the line SS in FIG. 19;

FIG. 21 is a partially enlarged detailed view of FIG. 20;

FIG. 22 is a sectional view taken along line TT of FIG. 21;

[Explanation of symbols]

1A, 1B ... transformer box, 2 ... transformer, 2a, 2b, 2c
... Coil, 3A ... Front door, 3B ... Back door, 4 ... Exhaust fan, 5A, 5B ... Inlet, 6 ... Electrical room, 7A ... Shield plate,
7B: shielding frame, 8A, 8B, 8C: air volume adjusting plate, 9A,
9B: air reservoir, 11: iron core, 12: primary coil, 13: secondary coil, 14, 15, 16 ... ventilation path.

Claims (6)

[Claims] An electric device is housed in a box whose outer periphery is closed, and a cooling air suction port is formed at a lower portion of the box.
In a forced-ventilation electric equipment box provided with an exhaust fan at an upper end of the box, an outer periphery of a side surface of the electric equipment is loosely fitted to an inner periphery, and an air reservoir for storing the cooling air sucked from the suction port is lowered. A forced ventilation type electric equipment box, wherein a shielding member formed on the side is laterally provided inside the box body. 2. The forced-ventilated electric equipment box according to claim 1, wherein the electric equipment is a transformer, and an inner periphery of the shield is opposed to a lower end of a coil of the transformer. 3. The forced-ventilated electric equipment box according to claim 1, wherein the shielding tool is a square-shaped shielding plate. 4. The box according to claim 2, wherein the shielding member has a rectangular tube shape, and an upper end thereof is opposed to a lower end of the coil of the transformer. 5. The gap adjusting tool according to claim 2, wherein a gap adjusting tool protrudes from a portion of an inner circumference of the shielding tool facing a curved surface of an outer circumference of the coil of the transformer. The forced ventilation type electric equipment box described in any of them. 6. The forced ventilation type electric equipment box according to claim 1, wherein the box body has one of a back side and a side face adjacent to a wall of an installation place. .